Diaphragm for sound-reproducers.



APPLICATION FILED JAN. 31. 1910.

Patented Jan. 3, 1911.

WWW owes NATHAN STOWELL WAKEFIELD, OF LOS ANGELES, CALIFORNIA.

DIAPHRAGM FOR SOUND-REPRODUCERS.

Specification of Letters Patent.

Patented Jan. 3, 1911.

Application Med January 31, 1910. serial No. 541,201.

and inexpensive diaphragm possessing superior sound-reproducing properties.

Another object of the invention is to provide a diaphragm of the chambered type consisting of a novel arrangement of disks fastened together to form a unitary structure, and so designed as to reproduce the delicate tones or sound shades as well as accurately reproducing the volume and register of the original sound without the disagreeable, harsh metallic sounds 'as is. the

case with diaphragms commonly in use.

\Vith these objects in view and others, as will appear as the description proceeds, the invention ,comprises the various novel features of construction and arrangement of parts whiclr will be more fully described hereinafter and set forth with particularity in the claims appended hereto.

In the accompanying drawing, which illustrates one embodiment of the invention, Figure 1 1s a perspectlve View of the diaphragm. Fig. 2 is a perspective view showing the inner disk of the diaphragm in section. Fig. 3 1s a diametrlcal section of the diaphragm. Fig. 4 IS a plan view showing the'inner face of the inner disk. Fig. 5 is an enlarged sectional View of the central" portion of the diaphragm.

Similar reference characters are employed to designate corresponding parts throughout the views.

The diaphragm is .made of two comparatively thin? disks or plates 1 and 2 of wood or other suitable material, which are permanently secured together, by gluin or otherwise, accordin to the materia used, to constitute a unitary structure. The disk 1 forms the side of the dia hragm that is presented to the chamber of the sound box or the sound-reproducing device, while the disk 2 is disposed at the outside next to the stylus-carrying arm. One of the disks, prefperipheral flange 4 and a centralhub 5 will y be left. The disk 2 is perfectly fiat, both on its inner and outer surfaces, and is connected with the disk 1 by being glued to the flange 4 and hub 5. As shown in Fig. 5, the hub has a flat face 6 for providing a substantial area to whichthe disk 1 can be fastened. The outer face of the disk 1 is provided with a depression 7 directly at the hub 5, and the bottom of this depression is provided with an aperture 8 re istering with an aperture 9 in the disk 2 or receiving the screw which attaches the diaphragm to the stylus-carrying arm. The hub 5 has a threefold function, in that it mechanically connects the two disks together at the center, forms a sound post bet-ween the disks, and prevents the screw from being tightened to such an extent as to crack the disks in fastening the diaphragm to the stylus-carryin arm. The chamber disk 1 is provided with a plurality of apertures 10 ad acent to and concentrically arranged,

around the hub for the purpose of permitting the sounds to be carried from the diaphragm into the machine or sound box by the vibration of the diaphragm, which feature, together with the sounding post formed b the hub, conduce to the reproduction of c ear, round tones. When the diaphragm is made of Wood, it is preferable to glue the disks together with their grains extending transversely to each other so that one disk will serve to strengthen the other. Since the disks are connected together, both at the center and ed e of the diaphracgmha uce' comparatively durab e article is pro and one having a minimum thickness considering the box-like form.

From the foregoing description, taken in connection with the accompanying draw I ing, the advantages ofthe construction and of the method of operation will be readily apparent to those skilled in the art to whic the invention appertains, and While I have described the principle of operation of the invention, together with the device which I now consider to be the best embodiment thereof, I desire to have it understood that the device shown is merely illustrative, and

that such chan es may be made when desired as are wit in the scope of the claims ap ended hereto.

aving thus described the invention, what I claim as new, and desire to secure by Letters Patent, is

1. A chambered diaphragm for sound-reproducin devices consisting of a pair of parallel at-thin disks permanently secured together both at the center and periphery.

2. A diaphragm for sound-reproducing devises consisting of a pair of parallel flatthin disks permanently secured together at the center and around the periphery, one of the disks being chambered and having a plurality of apertures opening from the chamber.

3. A diaphragm for sound reproducers consisting of a flat disk havin one side hollowed out in the form of a sha low chamber surrounded by a peripheral flange, and a second disk bearin fiat against the flan e and rigidly secured t ereto, one of the dis s having a central hub forming a sounding post against which the other disks bears, the said hub and the disk bearing against the same bein adapted to have a astening means inserte therethrough for connecting the disks in fixed spaced relation and securing them to' a support.

4. A diaphragm for sound re roducers consisting of a air of flat para el disks, one of the disks Eaving a flat annular flan bearing against the inner face of the other disk and one of the disks having a central hub bearing flat against the opposed face of the other disk, the outer face of the disk having the hub being depressed within the areaof the hub to receive a securing device.

In testimony, that I claim the foregoing as in own, I have hereto afiixed my slgnature 1n the presence of two witnesses.

' NATHAN STOWELL WAKEFIELD- Witnesses:

' CLAUDE Mums,

Loom Woonwoam. 

